The present invention relates to brakes for bending sheet material, such as aluminum sheets and vinyl sheets which are used as siding for buildings and the like.
In U.S. Pat. No. 4,240,279 to Rhoades, a sheet metal brake is disclosed (known in the trade as a "trim brake"), wherein a lever, located on only one end of the trim brake, operates the brake. Consequently, after the user inserts the sheet metal into the machine, and before the operator can return to the appropriate end to activate the trim brake, the sheet metal often slips. If the metal has slipped but the user bends the metal anyway, the metal is bent "off-line". (Ideally, the metal is bent on a line that is parallel to the top and bottom of the sheet metal and perpendicular to the sheet metal's side. If the metal is bent "off-line", then the line is neither parallel nor perpendicular to its appropriate edge.) Afterwards, this sheet metal, which is bent off-line, is hard to install.
This problem might be eliminated if two persons were always available to operate the brake. One person could steady the metal to ensure that it did not slip. The second person could activate the brake. Unfortunately, there are rarely instances where an extra person can be spared to assist with this process.
Accordingly, it is the primary object of the present invention to provide an improved lever for trim brakes, which will eliminate the possibility that the sheet metal will be bent off-line.
It is another object to provide a brake lever extension which is lightweight and durable and does not interfere with the overall portability of the brake.
It is yet another object to provide a lever extension which does not require two persons to operate in order to prevent the sheet metal from slipping, such that the sheet is bent off-line.
It is still a further object to provide an improved trim brake lever which can open and close the brake from any point along the platform, rather than at just one end of the platform.
It is yet another object to provide an improved lever, commensurate with the above-listed objects, that can be retrofitted onto an existing machine, or, which can be manufactured as part of the original brake.
The above and other objects and advantages of this invention will become more readily apparent when the following description is read in conjunction with the accompanying drawings.